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    This question is really confusing me

    Using your knowledge of Hooke's law and Newton's second law determine the period T of a trolley moving in Simple Harmonic Motion in terms of the force constant k and the mass m of the trolley

    I did
    -kx = ma

    a = -(2pief)^2 x
    therefore -kx = m[-(2pief)^2 x]
    minuses and x cancel
    so k= m[2pie(1/T)]^2
    k = 4pie^2m/T^2
    T^2 = 4pie^2m/k
    T = 2pie root(m/k)

    but the answer is T = 2pie root(k/m)

    WHat am I doing wrong??? please help me
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    Any1??
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    is this at A level?
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    (Original post by alithegreat)
    This question is really confusing me

    Using your knowledge of Hooke's law and Newton's second law determine the period T of a trolley moving in Simple Harmonic Motion in terms of the force constant k and the mass m of the trolley

    I did
    -kx = ma

    a = -(2pief)^2 x
    therefore -kx = m[-(2pief)^2 x]
    minuses and x cancel
    so k= m[2pie(1/T)]^2
    k = 4pie^2m/T^2
    T^2 = 4pie^2m/k
    T = 2pie root(m/k)

    but the answer is T = 2pie root(k/m)

    WHat am I doing wrong??? please help me

    F = (-) kx and F = ma
    Therefore ma = (-) kx
    ω2 = k /m
    T = 2π (m/ k)

    so the answer is right, must be some error on your books end

    edit - this is from a specimen paper for physics i copy and pasted

    http://www.ocr.org.uk/download/asses..._unit_g484.pdf

    Take a look for it yourself.
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    You didn't do anything wrong. Your answer is correct, the answer given to you is wrong. The period of a mass attached to a helical spring doing SHM is T=2pie x root(m/K). Its a formula often given in textbooks and formula booklets.
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    thnx guys i guess the ms is wrong
 
 
 
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